Metal ribbon making



June 12, 1934. DEwALD 1,962,896

METAL RIBBON MAKING Filed Jan. 8, 1951 s Sheets-Sheet 1 I INVENTOR 'r ATTORNEYS June "12, 1934. E A D'EwALb' 1,962,896

METAL RIBBON MAKING Filed Jan. 8, 1931 s Sheets-Sheet 2 ATTORNEYS June 12, 1934. DEwALD 1,962,895

METAL RIBBON MAKING Filed Jan. 8, 1931 3 Sheets-Sheet 3 INVENTOR I BY 2.44441 77w WWv-M 71/: ATTORNEYS Patented June 12, 1934 UNITED" STATES PATENT OFFICE METAL RIBBONMAKINQ Application January 8,

8 Claims.

This invention relates to the manufacture of metal ribbon and more particularly concerns a method and means for forming a metallic band or ribbon by flattening a metallic wire.

One type of heat exchanger or condenser which has gone into extensive use employs fluid ducts or pipes having fins spirally wound on the surfaces thereof. 'I'hese fins are customarily formed of a continuous flat strip or ribbon of heat conductive metal, such as copper, which is wound edgewise on the pipe by suitable means. It is highly desirable that the metallic ribbons so employed be of uniform thickness, strength and flexibility in order that the winding thereof on the pipes may be economically and satisfactorily effected by automatic machinery.

In accordance with the present invention, it is proposed to provide an improved machine for flattening round metallic wire into a continuous strip or ribbon for use in forming the heat conductive fins of a heat exchanger unit or in other applications. A particular object of the inven tion resides in the provision of a machine of thischaracter which is so devised and arranged that the wire from which the metallic ribbon is formed is first accurately straightened and the formed ribbon is handled in such a manner that any undesirable kinking, buckling or other injury thereto is avoided. In general, the invention has for its object, the provision of an improved method of forming a straight continuous metallic ribbon of uniform thickness, as well as the provis'ion of improved apparatus for carrying this method into effect.

Various additional objects, advantages and characteristic features of the invention will become apparent as the description thereof progresses.

In general, the method of the invention is carried out by first-straightening the round wire from which the strip is to be formed and then flattening the wire between suitable pressing rolls, the flat ribbon being maintained under tension for a considerable distance of travel after leaving the pressing rolls. The apparatus employed in carrying this method into efiect preferably includes pressing rolls which may be accurately aligned and adjusted to form a strip of any desired thickness, and a set of tension applying rolls disposed in a common plane with their axes in parallel relation, between which the formed ribbon is passed and by means of which the ribbon is subjected to a suitable tension without danger of any lateral bending, cooking, or tearing of the ribbon. The apparatus preferably in- 1931, Serial No. 507,325

cludes means for limiting the amount of tension placed on the formed metallic ribbon by the tension rolls.

The invention will be best understood by reference to the accompanying drawings in which oneform of apparatus embodying the invention and suitable for carrying out the improved method has been illustrated. In the drawings;

Figure 1 is a side'elevation of a metallic ribbon forming machine embodying the invention;

Fig. 2 is a left end elevation of the machine shown in Fig. 1;

Fig. 3 is a sectional view taken along the line 33 of Fig. 1 and viewed in the direction of the arrows;

Fig. 4 is a sectional view taken along the line 44 of Fig. 1 and viewed in the direction of the arrows;

Fig. 5 is a simplified disclosure of the wire flattening and ribbon stretching elements of the machine;

Fig. 6 is a sectional view of one of the wire straightening rollers; and

Fig. 7 is a partial sectional view of the wire flattening or pressing rolls.

Referring to the drawings and more particularly to Figs. 1 through 5, the disclosed embodiment of my improved metallic ribbon forming machine comprises generally a plurality of wire straightening rollers '7, 8 and 9, a pair of wireflattening rolls 10 and 11, a plurality of ribbon stretching or tension rolls 12, 13, 14, 15 and 16 and a weighted tension regulating roll 17. All of these wire and ribbon carrying rolls and rollers are disposed with their cylindrical surfaces in alignment and their axes in parallel relationship. The machine comprises a pair of parallel frame members 18 carried by a base 19 and connected at their upper ends by a head 20. The frame members 18 are respectively provided with aligned vertically extending rectangular openings or keyways 21, and two bearing blocks 22 and 23 are slidably supported, one above the other, in each of these openings as shown in Figs. 1 and 4. The blocks 22 and 23 carry bearings 24 and 25 respectively, which bearings may be of the roller or other anti-friction type, if desired. A shaft 26 carrying thelower wire flattening or pressing roll 11 is journaled in the bearings 24 of the lower blocks 23 and a parallel shaft 27 carrying the upper wire flattening or pressing r011 10 is journaled in the bearings 25 of the upper blocks 22. A plurality of compressed coiled springs 28 are interposed in suitable recesses between the blocks 22 and 23 to hold these blocks apart, as shown in Figs. 1 and 3. The lower wire flattening roll 11, together with its shaft 26 and blocks 23, is supported on a pair of spaced rollers 29, rotatably carried by a U-shaped member 30 which rests upon the brackets 31 of the frame members 18. A pair of similar spaced rollers 32 bear upon the upper pressing roll 10, these rollers being rotatably carried by a frame member 33 which is movable vertically with respect to the frame members 18. The frame member 33 is arranged to apply pressure, to the upper bearing blocks 22 as well as to the roll 10, and to this end, a pair of vertically adjustable screw threaded posts 34 extend between the frame member 33 and the upper surfaces of the blocks 22, as shown in Figs. 1 and 3.

It is preferred to provide means for variably adjusting the distance between the wire flattening rolls 10 and 11, and in the disclosed embodiment, this is accomplished by altering the vertical position of the frame member 33 and thereby compressing or releasing the springs 28 to move the rolls 10 and 11 closer together or farther apart. Two screw threaded vertical studs 35 rest on the upper surface of the frame member 33 and are threadedly engaged adjacent their upper ends by the nuts 36 which bear on the under surface of the machine head 20. The peripheral surfaces of the nuts 36 are provided with gear teeth as shown, and a pinion 37 carried on a shaft 38 journaled in the head 20 engages both of these nuts. The upper end of the shaft 38 carries a gear wheel 39 which is engaged by a pinion 40 driven by a hand crank 41. It will be seen that the rotation of the pinion 40 by the crank 41 imparts rotation to the nuts 36 and consequently depresses or releases the frame member 33 and. the blocks 22 carrying the upper pressing roll 10.

Considerable heat is generated in flattening the round metal wire into a ribbon between the rolls 10 and 11, and means are accordingly provided to permit the cooling of these rolls. As shown in Figs. 3, 5 and 7, the shafts 26 and 2'7 are drilled axially and the rolls 10 and 11 are formed of an inner core 42 and outer tire 43 held on the core by the flanged collars 44. Cooperating grooves 45 and 46 are formed respectively in the outer surface of the core 42 and the inner surface of the tire 43, and these grooves form a circular passage 47 for a cooling fluid beneath the tire 43. The axial openings 48 in the shafts 26 and 2'7 are connected to the passages 47 by the radial passages 49, as shown in Figs. 5 and 7. A suitable cooling fluid such as water is conducted through the two shafts 26 and 27 in series by means of the pipes 50, 51, and 52 which communicate with the axial shaft passages 48 through the stationary caps 53 on the shaft ends, as shown in Fig. 2.

The wire straightening rollers 7, 8 and 9 are preferably provided with circumferential wire grooves 54 as shown in Fig. 6. Any desired number of wires may be simultaneously flattened in the machine, and in the embodiment shown, two wires are thus treated. According, two wire grooves 54 are provided in each of the rollers 7, 8 and 9. The rollers 7, 8 and 9' are rotatably supported on a bracket 55 secured to one of the frame members 18, and are disposed in staggered relation as shown in Figs. 1 and 5. A wire guide block 56 having a pair of spaced parallel wire guides or bushings 57 mounted therein is fixed adjacent the first wire straightening roller 7, as shown in Figs. 1 and 2 anda similar block 86 carrying the wire guides 8'7 is fixed adjacent the last roller 9, as shown in Fig. 4.

The first ribbon stretching or tension roll 12 is carried by a shaft 58 journaled in the frames 1.8 and the remaining tension rolls 13, 14, 15 and 16 are suitably rotatably mounted on an outward- 1y extending frame 59. It will be noted by reference to Figs. 1 and 4 that although the cylindrical surfaces of the rolls 12 through 16 are in alignment, the axes of these rolls are staggered, the axes of the rolls 13 and 15 being below the plane of the axes of the rolls 12, 14 and 16. This particular arrangement of the tension rolls is not essential to the invention, but it is preferred that the rolls lie with their cylindrical surfaces in alignment and with their axes in spaced and parallel relationship. Intermeshing gear wheels 60, 61, 62 and 63 of equal size are respectively fixed to the shaft of the rolls 13, 14, 15 and 16, and a slightly larger gear wheel 64, meshing with the gear wheel 60, is fixed to the shaft 58 of the roll 12. Since all of the tension rolls are of the same diameter, the peripheral velocity of the rolls 13, 14, 15 and '16 is slightly higher than that of the roll 12.

A weighted tension regulating roll 1'7 is carried adjacent the last ribbon stretching or tension roll 16 as shown in Figs. 1 and 4. The roll 17 may be pressed downwardly against the ribbons 88 by any suitable means. As shown, the roll 17 is carried by a pair of L-shaped arms 66. pivotally connected at 67 to the frame 59 and weighted by the disc 68. 4

The machine may be driven by an electric motor or any other suitable prime mover connected through the pinion 69 to the gear wheel '70. The gear wheel '70 is connected by a shaft 71 to a pinion 72 which engages a gear wheel '73 fixed to a shaft '74. Driving power is, transmitted from the shaft 74 to the lower pressing roll shaft 26 through the gears 75, 76 and 77, and to the upper pressing roll shaft 27 through gears '78 meshing with the gear 7'7, as shown in Figs. 2 and 3. A gear wheel 79 is fixed to the shaft 26 and serves to drive the roll 12 and the connected rolls 13 through 1'6 through an idler gear 80 and the gear wheel 81 fixed to the shaft 58 of the roll 12. The

on the shaft 26. In this manner, the peripheral velocity of the roll 12 and the rolls 13 through The idler 16 relative to that of the wire flattening rolls 10 machine, two strands of wire 85 are threaded through the wire guides 57 and pass over the wire straightening roller '7, under the roller 8 and over the roller 9, these wires lying in the grooves 54 of these rollers. The wires 85 are then passed through the wire guides 87 and between the tires 43 of the wire flattening rolls 10 and 11. In passing between the rolls 10 and 11, the wires 85 are flattened into ribbons 88 as best shown --in Figs. 4 and 7 The flat ribbons 88.are next passed over the roll 12, under the roll 13, over theroll 14, under the roll 15 and over the roll 16, the weighted roll 17 bearing on the upper surfaces of the ribbons adjacent the roll 16, as shown in Fig. 5. The formed and straightened ribbons 88 equivalent means by any suitable reeling device.

As the wires 85 pass over the straightening rollers '7, 8 and 9, all kinks, bends or other irregularities are removed therefrom by the successive bending of the wires between these rollers. The wires 85 are thus delivered to the flattening rolls 10 and 11 in a straight and uniform condition and in parallel relation, as shown in Fig. 4. 1

As explained above, the driving gears are so proportioned and arranged that the peripheral velocity of the roll 12 is higher than that of the wire flattening rolls 10 and 11, and the peripheral velocity of the rolls 13 through 16 is higher than that of the. roll 12. Accordingly, the rolls 12 through 16 slip on the ribbons 88 and place considerable tension thereon as the ribbons are drawn out from between the flattening rolls 10 and 11. The application of this tension is of considerable importance. If no tension were applied to the formed ribbons as they leave the flattening rolls, the ribbons would wave and kink due in part to the uneven expansion of the metal as a result of the heat generated by the flattening operation. The stretching of the ribbons at this point not only avoids this waving tendency,

but also holds the ribbons straight against any tendency toward lateral waving or buckling until after the ribbons have cooled. The several successive vertical bends of the ribbons as they pass over and under the staggered rolls 12 through 16 remove any vertical waves or bends therefrom.

,The use of a plurality of driven stretching or tension rolls having their cylindrical surfaces in alignment with their axes parallel, permits the application of considerable tension to the ribbons without imposing any lateral bending stresses thereon. Thus, if each ribbon were wound several times about a single roll, the successive turns of the ribbon would be cocked and would crowd together, one beneath the other, resulting in the cutting or other injury of the ribbon. With the arrangement of the present invention, the ribbons are maintained in a straight path and at the same time, an extended area of the ribbons is frictionally engaged by the several rolls and a considerable tension is consequently applied thereto.

. The amount of tension placed on the ribbons 88, by the rolls 12 through 16 is controlled by the weighted roll 1'7. This roll takes up any back lash in the ribbons at the point where they leavethe tension rolls and maintains an even pressure between the ribbons and the roll surfaces, thereby controlling the friction between the tension rolls and the ribbons and governing the degree of tension imposed upon the ribrality of tension rolls disposed with their oppo-- site end faces lying respectively in common planes and having their axes disposed in parallel staggered relation and relatively spaced along the path of travel of the ribbon, means for driving said wire flattening rolls at a predetermined peripheral velocity and means for driving said tension rolls at a higher peripheral velocity.

tension rolls respectively engaging the oppositeflat surfaces of the ribbon leaving said flattening rolls, and means for driving said tension rolls at a higher peripheral velocity than said flattening rolls.

3. In a machine 'for forming a metallic wire into a flat metallic ribbon, in combination with a pair of cooperating members for flattening the wire, means for maintaining the formed ribbon under tension comprising at least two staggered rolls for respectively engaging the opposite flat surfaces of the formed ribbon, said rolls having parallel axes spaced along the path of travel of the ribbon and having their opposite end faces lying respectively in common planes and means for driving said rolls at a peripheral velocity such that the formed ribbon is maintained under tension.

4. In a machine for forming a metallic wire into a flat metallic ribbon, in combination with a pair of cooperating members for flattening the wire, means for maintaining the formed ribbon under tension comprising a plurality of tension rolls for engaging the opposite flat surfaces of the formed ribbon, said rolls having opposite end faces lying respectively in common planes and having their axes staggered parallel, and relatively spaced alongthe path of travel of the ribbon, means for driving said rolls at a peripheral velocity such that the formed ribbon is maintained under tension and means for maintaining a uniform pressure between the surfaces of said ribbon and said tension rolls.

5. In a machine for forming a metallic wire into a flat metallic ribbon, in combination with a pair of cooperating rolls for flattening the wire and means for driving said rolls, means for withdrawing the formed ribbon from said flattening rolls under tension and maintaining the ribbon under tension for a considerable distance of travel comprising a row of spaced staggered tension rolls having opposite end faces lying respectively in common planes with their axes parallel, the adjacent rolls in said row respectively engaging opposite flat surfaces of the ribbon whereby the ribbon is subjected to a plurality of reverse bends in passing over said rolls and means for driving said tension rolls at a higher peripheral velocity than said flattening rolls.

6. In a machine for forming a metallic wire into a flat metallic ribbon, in combination with a pair of cooperating rolls for flattening the wire and means for driving said rolls, means for withdrawing the formed ribbon from said flattening rolls under tension and maintaining the ribbon under tension for a considerable distance of travel comprising a row of spaced tension rolls having opposite end faces lying respectively in common planes and their axes parallel, the adjacent rolls in said row respectively engaging the opposite flat surfaces of the ribbon whereby the ribbon is subjected to a plurality of reverse bends in passing over said rolls, means for driving said tension rolls at a higher peripheral velocity than said flattening rolls and a weighted tension regu-v lating roll engaging the ribbon adjacent said tension rolls and acting to maintain a uniform pressure between the ribbon and said tension rolls.

7. In a machine for forming and straightening bon forming means and means for withdrawing a ribbon from said forming means under tension, comprising a row of staggered tension rolls having opposite end faces lying'respectively in common planes and having parallel axes, the adjacent rolls of said row respectively engaging the upper and lower surfaces of the ribbon as it leaves the forming means whereby the formed ribbon is subjected to a succession of reverse bends, means for driving said tension rolls at a peripheral velocity higher than the velocity of the ribbon through said forming means, a tension regulating roll engaging said ribbon as it leaves the last of said tension rolls and means for pressing said tension regulating roll against the ribbon whereby a uniform pressure is maintained between the ribbon and the tension rolls.

EDWARD A. DEWALD. 

